package javacore.net.javacore;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.Scanner;

/**
 * This program implements a multithreaded server that listens to port 8189 and echoes back
 * all client input.
 * 
 * @author Cay Horstmann
 * @version 1.20 2004-08-03
 */
public class ThreadedEchoServer
{
    public static void main(String[] args)
    {
        try
        {
            int i = 1;
            ServerSocket s = new ServerSocket(8189);

            while (true)
            {
                Socket incoming = s.accept();
                System.out.println("Spawning " + i);
                Runnable r = new ThreadedEchoHandler(incoming);
                Thread t = new Thread(r);
                t.start();
                i++;
            }
        }
        catch (IOException e)
        {
            e.printStackTrace();
        }
    }
}

/**
 * This class handles the client input for one server socket connection.
 */
class ThreadedEchoHandler implements Runnable
{
    /**
     * Constructs a handler.
     * 
     * @param i the incoming socket
     * @param c the counter for the handlers (used in prompts)
     */
    public ThreadedEchoHandler(Socket i)
    {
        this.incoming = i;
    }

    @Override
    public void run()
    {
        try
        {
            try
            {
                InputStream inStream = this.incoming.getInputStream();
                OutputStream outStream = this.incoming.getOutputStream();

                Scanner in = new Scanner(inStream);
                PrintWriter out = new PrintWriter(outStream, true /* autoFlush */);

                out.println("Hello! Enter BYE to exit.");

                // echo client input
                boolean done = false;
                while (!done && in.hasNextLine())
                {
                    String line = in.nextLine();
                    out.println("Echo: " + line);
                    if (line.trim().equals("BYE"))
                    {
                        done = true;
                    }
                }
            }
            finally
            {
                this.incoming.close();
            }
        }
        catch (IOException e)
        {
            e.printStackTrace();
        }
    }

    private Socket incoming;
}
